(CNN) -- Whoever killed six people in a Memphis, Tennessee, home may still be on the loose, police said Tuesday. They asked the community for help in solving the slayings.
Police and fire units responded Monday after six people were killed in Memphis, Tennessee.
Police found six people -- two men, two women and two boys -- dead in a home in a north Memphis neighborhood Monday, said Memphis police Lt. Joe Scott.
Three other children who were wounded in the home were taken to a hospital.
Scott did not release the names of the victims. He said there was no sign of forced entry into the home, and evidence at the scene indicated that the killer or killers left the house.
Detectives were trying to determine the day of the killings, which could have occurred as early as Saturday, Scott said.
He said police had not developed a suspect and need people to come forward with information.
"We need the community's help," he said. "These were children that were brutally killed. We know that there are people out there that heard things, saw something. This is a stain on our community. We really need the community's help to solve this."
The four dead adults were shot and the two dead children were stabbed, sources told CNN affiliate WMC-TV.
The wounded children -- a 7-year-old boy, a 10-month-old girl and a 4-year-old whose gender wasn't immediately known -- were transported to Le Bonheur Children's Medical Center. They were treated for gunshot wounds, said hospital spokeswoman Jennilyn Utkov, who said she did not have any additional information about their conditions.
At least one of the wounded children also was stabbed, police told the Commercial Appeal newspaper. The newspaper reported Tuesday that two of them were in very critical condition and one was in serious condition.
A neighbor told CNN Tuesday that he heard gunshots coming from the house Saturday night.
"I heard about six or seven shots," said Wayne Bolden, a landscaper who said he lives across the street from the home where the killings occurred. "I did not call the police because you always hear shooting in this neighborhood. Now I wish I would have called."
He said he did not see any movement at the home the next day. The two cars, a van and a passenger car, never moved.
Monday, he saw many police cars at the home and heard about the killings, he said.
Bolden said a family that included a man, a woman and five or six children moved into the home about five months ago.
"I did not know him by name," Bolden said of the man. "But the kids were always out playing, and he would barbecue outside on his front porch."
A prayer service was held for the victims Tuesday morning at the family's nearby church, said Keith Norman, senior pastor at First Baptist Church.
He said he had been asked by the police to counsel the family members of the victims. Another prayer service was scheduled for 6 p.m., he said, and some of the victims' family members are expected to attend.
"There are multiple families affected by this," said Norman, who said he did not want to speak about what led to the killings. "We are just praying for the family members and trying to help them get through this."
Police do not know what was behind the violence, the Commercial Appeal newspaper reported.
"We just don't know the motive or cause of death, but we do have four adults and two children [dead]," Memphis police Lt. Jerry Guin told the paper.
Rob Robinson told the Commercial Appeal that he was the landlord for the brick, single-family house that rented for $550 per month.
"They were very nice, very polite to me," Robinson told the paper of the residents.
"It's kind of surprising, actually. I've never had any trouble with them, no damage to the property. They paid their rent and even helped with repairs and stuff."
Neighbor Leo Baker told WMC-TV he has lived nearby for 10 years but did not know the residents of the home.
"It's sad you come home to find out something like this has gone on," Baker said. "It's kind of sad, and scary too."
Video footage showed emergency vehicles on the scene, with people embracing in rainy weather outside police tape surrounding the home.
"I've been on a scene where there were one or two or three [victims], but I don't remember anything this large," Guin told the Commercial Appeal.
The newspaper reported that the shooting appeared to be the city's deadliest mass killing since 1973, when 28-year-old David Sanders randomly shot and killed five people before being shot dead by police.
In 2000, police said firefighter Frederick Williams confessed to a shooting in Memphis in which four people were killed -- his wife, a sheriff's deputy and two fellow firefighters. E-mail to a friend